GDP
A substantial chunk of Sindh’s GDP is attributed to Karachi (the GDP of Sindh as a percentage of Pakistan’s total GDP has traditionally hovered around 29%/30%). Karachi’s GDP is around 20% of the total GDP of Pakistan. A PricewaterhouseCoopers study released in 2009, which surveyed the 2008 GDP of the top cities in the world, calculated Karachi’s GDP (PPP) to be $78 billion (projected to be $193 billion in 2025 at a growth rate of 5.5%). It confirmed Karachi’s status as Pakistan’s largest economy, well ahead of the next two biggest cities Lahore and Faisalabad, which had a reported GDP (PPP) in 2008 of $40 billion and $14 billion, respectively. Karachi's high GDP is based on its large industrial base, with a high dependency also on the financial services sector. Textiles, cement, steel, heavy machinery, chemicals, food, banking and insurance are the major industrial sectors contributing to Karachi's GDP.
Revenue collection
In line with its status as a major port and the country's largest metropolis, it accounts for a lion's share of Pakistan's revenue generation. According to the Pakistan Federal Board of Revenue's 2006-2007 year book tax and customs units in Karachi was responsible for 46.75% of direct taxes, 33.65% of federal excise tax, and 23.38% of domestic sales tax. Karachi also accounts for 75.14% of customs duty and 79% of sales tax on imports. Therefore, Karachi collects a significant 53.38% of the total collections of the Federal Board of Revenue, out of which 53.33% are customs duty and sales tax on imports. Revenue collected from Karachi includes revenue from some other areas since the Large Tax Unit (LTU) Karachi and Regional Tax Offices (RTOs) Karachi, Hyderabad, Sukkur and Quetta cover the entire province of Sindh and Baluchistan.[1] Karachi's indigenous contribution to national revenue is 25%.